diff --git a/config/config.go b/config/config.go
index b3ac8cbc6..ec851f3fe 100644
--- a/config/config.go
+++ b/config/config.go
@@ -1,5 +1,6 @@
 package config
 
+// Mailroom is the global configuration
 var Mailroom *Config
 
 func init() {
@@ -15,15 +16,16 @@ type Config struct {
 	Elastic    string `help:"URL for your ElasticSearch service"`
 	Version    string `help:"the version of this mailroom install"`
 	LogLevel   string `help:"the logging level courier should use"`
-	SMTPServer string `help:"the smtp configuration for sending emails ex: smtp://user%40password@server:port/?from=foo%40gmail.com"`
 
 	BatchWorkers   int `help:"the number of go routines that will be used to handle batch events"`
 	HandlerWorkers int `help:"the number of go routines that will be used to handle messages"`
 
 	RetryPendingMessages bool `help:"whether to requeue pending messages older than five minutes to retry"`
 
-	MaxValueLength    int `help:"the maximum size in characters for contact field values and run result values"`
-	MaxStepsPerSprint int `help:"the maximum number of steps allowed per engine sprint"`
+	WebhooksTimeout   int    `help:"the timeout in seconds for webhook calls from engine"`
+	SMTPServer        string `help:"the smtp configuration for sending emails ex: smtp://user%40password@server:port/?from=foo%40gmail.com"`
+	MaxStepsPerSprint int    `help:"the maximum number of steps allowed per engine sprint"`
+	MaxValueLength    int    `help:"the maximum size in characters for contact field values and run result values"`
 
 	LibratoUsername string `help:"the username that will be used to authenticate to Librato"`
 	LibratoToken    string `help:"the token that will be used to authenticate to Librato"`
@@ -50,17 +52,19 @@ type Config struct {
 // NewMailroomConfig returns a new default configuration object
 func NewMailroomConfig() *Config {
 	return &Config{
-		DB:                "postgres://temba:temba@localhost/temba?sslmode=disable",
-		DBPoolSize:        36,
-		Redis:             "redis://localhost:6379/15",
-		Elastic:           "http://localhost:9200",
-		BatchWorkers:      4,
-		HandlerWorkers:    32,
-		LogLevel:          "error",
-		Version:           "Dev",
+		DB:             "postgres://temba:temba@localhost/temba?sslmode=disable",
+		DBPoolSize:     36,
+		Redis:          "redis://localhost:6379/15",
+		Elastic:        "http://localhost:9200",
+		BatchWorkers:   4,
+		HandlerWorkers: 32,
+		LogLevel:       "error",
+		Version:        "Dev",
+
+		WebhooksTimeout:   15,
 		SMTPServer:        "",
-		MaxValueLength:    640,
 		MaxStepsPerSprint: 100,
+		MaxValueLength:    640,
 
 		S3Endpoint:         "https://s3.amazonaws.com",
 		S3Region:           "us-east-1",
diff --git a/goflow/engine.go b/goflow/engine.go
index 177abc2f8..7a79031ca 100644
--- a/goflow/engine.go
+++ b/goflow/engine.go
@@ -16,27 +16,16 @@ import (
 	"github.com/shopspring/decimal"
 )
 
-var httpClient *http.Client
 var eng, simulator flows.Engine
-var engInit, simulatorInit sync.Once
+var engInit, simulatorInit, webhooksHTTPInit sync.Once
+
+var webhooksHTTPClient *http.Client
+var webhooksHTTPRetries *httpx.RetryConfig
 
 var emailFactory engine.EmailServiceFactory
 var classificationFactory engine.ClassificationServiceFactory
 var airtimeFactory engine.AirtimeServiceFactory
 
-func init() {
-	// customize the default golang transport
-	t := http.DefaultTransport.(*http.Transport).Clone()
-	t.MaxIdleConns = 32
-	t.MaxIdleConnsPerHost = 8
-	t.IdleConnTimeout = 30 * time.Second
-	t.TLSClientConfig = &tls.Config{
-		Renegotiation: tls.RenegotiateOnceAsClient, // support single TLS renegotiation
-	}
-
-	httpClient = &http.Client{Transport: t, Timeout: time.Duration(15 * time.Second)}
-}
-
 // RegisterEmailServiceFactory can be used by outside callers to register a email factory
 // for use by the engine
 func RegisterEmailServiceFactory(factory engine.EmailServiceFactory) {
@@ -63,10 +52,10 @@ func Engine() flows.Engine {
 			"X-Mailroom-Mode": "normal",
 		}
 
-		retries := httpx.NewRetryDelays(3, 10)
+		httpClient, httpRetries := webhooksHTTP()
 
 		eng = engine.NewBuilder().
-			WithWebhookServiceFactory(webhooks.NewServiceFactory(httpClient, retries, webhookHeaders, 10000)).
+			WithWebhookServiceFactory(webhooks.NewServiceFactory(httpClient, httpRetries, webhookHeaders, 10000)).
 			WithEmailServiceFactory(emailFactory).
 			WithClassificationServiceFactory(classificationFactory).
 			WithAirtimeServiceFactory(airtimeFactory).
@@ -85,6 +74,8 @@ func Simulator() flows.Engine {
 			"X-Mailroom-Mode": "simulation",
 		}
 
+		httpClient, _ := webhooksHTTP() // don't do retries in simulator
+
 		simulator = engine.NewBuilder().
 			WithWebhookServiceFactory(webhooks.NewServiceFactory(httpClient, nil, webhookHeaders, 10000)).
 			WithClassificationServiceFactory(classificationFactory).   // simulated sessions do real classification
@@ -97,6 +88,27 @@ func Simulator() flows.Engine {
 	return simulator
 }
 
+func webhooksHTTP() (*http.Client, *httpx.RetryConfig) {
+	webhooksHTTPInit.Do(func() {
+		// customize the default golang transport
+		t := http.DefaultTransport.(*http.Transport).Clone()
+		t.MaxIdleConns = 32
+		t.MaxIdleConnsPerHost = 8
+		t.IdleConnTimeout = 30 * time.Second
+		t.TLSClientConfig = &tls.Config{
+			Renegotiation: tls.RenegotiateOnceAsClient, // support single TLS renegotiation
+		}
+
+		webhooksHTTPClient = &http.Client{
+			Transport: t,
+			Timeout:   time.Duration(config.Mailroom.WebhooksTimeout) * time.Second,
+		}
+
+		webhooksHTTPRetries = httpx.NewRetryDelays(3, 10)
+	})
+	return webhooksHTTPClient, webhooksHTTPRetries
+}
+
 func simulatorEmailServiceFactory(session flows.Session) (flows.EmailService, error) {
 	return &simulatorEmailService{}, nil
 }